The dielectric constant of ferroelectric materials can be expressed by the equation

More Questions from Materials and Components

• If a capacitor C having selectivity factor Q is scaled down in all its dimensions by a factor K without any altering the dielectric material, the new capacitor will have capacitance and selectivity as
• Which solid dielectric has highest temperature limit?
• Assertion (A): An electron having charge - e and mass m and lying in an electric field E is subjected to an acceleration - (e/m) E. Reason (R): If there are n electrons/m3 moving with velocity vx and each electron has a charge - e, the current density J = - n evx.
• Assertion (A): Orbital magnetic moment of an electron in an atom is of the order of 1 Bohr magneton. Reason (R): 1 Bohr magneton = 9.27 x 10-24 A/m2.
• When a pentavalent impurity is added, the semiconductor becomes
• For a polyatomic gas, the equation relating dielectric constant ∈r with molecular properties is
• Assertion (A): For most metals, Fermi energy EF is less than 10 eV. Reason (R): Fermi level of a metal is given by EF = 3.64 x 10-19 (n)2/3 where n is number of free electrons/m3 of metal.
• The relaxation time of electrons in a metal is of the order of
• As regards ∈0 and ∈r (absolute and relative permittivity)
• An electron is moving in a circular orbit of radius R at angular velocity ω0 in a field free space. If a magnetic field B is created, the velocity of electron ω will be given by the equation

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